Library Guides: Choosing & Evaluating Journals, Publishers & Conferences: Metrics

Metrics

A number of different numerical rankings for journals exist. This section contains information on several different numerical methods used to measure a journal's importance. Additional information on metrics is available in Science Metrics, Nature Special Issue, June 16, 2010.

Science Metrics
Nature Publishing, 2010. Science metrics. Nature, 16 June 2010
Impact: The Search for the Science that Matters
Nature Publishing, 2013. Impact: The Search for the Science that Matters. Nature Special Issue 17 October 2013
Spurious Alternative Impact Factors: The Scale of the Problem from an Academic Perspective
Gutierrez, Fredy R.S., Beall, Jeffrey and Forero, Diego A., 2015. Spurious alternative impact factors: The scale of the problem from an academic perspective. BioEssays, Vol. 37, no. 5, p. 1521-1878

A number of different journal ranking measures exist. They are described in the following boxes:

Impact Factor

The Thomson-Reuters (formerly ISI) Impact Factor is the oldest quantitative measure of journal prestige. It is calculated based on the number of citations during a given year to journal articles published in the previous two years. There are some concerns about using the Impact Factor to judge research, because it varies by discipline and type of article (for example, review articles are usually cited more than research articles). See the article by Seglen linked below. In addition, an article that is scientifically inaccurate could be cited by other articles that are critical of the methods and techniques used in the inaccurate article.

NOTE OF CAUTION: Some disreputable publishers may claim that they have an Impact Factor. The Impact Factor that matters most is the one reported by Thomson-Reuters in Journal Citation Reports (JCR), which is based on titles that are indexed in Science Citation Index and Social Science Citation Index. WIU does not provide access to JCR, but it is possible to check the title lists for Science Citation Index and Social Science Citation Index to see if the journal is indexed. If it is not, then the claimed "Impact Factor" is probably not valid.

The Thomson-Reuters Impact Factor
A website that contains the text of an essay on the Thomson-Reuters Impact factor that was published in Current Contents, June 1994.
Why the Impact Factor of Journals should not be used for Evaluating Research
Seglen, Per O., 1997. Why the impact factor of journals should not be used for evaluating research. BMJ (British Medical Journal), vol. 314, no. 7079, pages 498-502. (Available through PubMed Central)
Science Citation Index Titles by Subject
Science Citation Index is published by Clarivate Analytics. This site can be used to view a list of titles related to a specific subject that are indexed in Science Citation Index.
Social Science Citation Index Titles by Subject
Social Science Citation Index is published by Clarivate Analytics. This site can be used to view a list of titles related to a specific subject that are indexed in Social Science Citation Index.
Arts & Humanities Citation Index Titles by Subject
Arts & Humanities Citation Index is published by Thomson-Reuters. This site can be used to view a list of titles related to a specific subject that are indexed in Arts & Humanities Citation Index.

Eigenfactor

Eigenfactor
The Eigenfactor is a measure of a journal's importance to the scientific community. It is based on the Thomson-Reuters' Impact Factor, so any title with an Eigenfactor must be included in Journal Citation Reports and indexed in Science Citation Index and Social Science Citation Index. The Eigenfactor website can be used to search for a journal by discipline or title (actually by the title's abbreviation). It also provides information on a journal's Article Influence, which is a measure of the influence of the articles published in a journal during the previous 5 years of publication.

h-Index

h-Index
The h-Index was proposed by J.E. Hirsch in a paper published in the Proceedings of the National Academy of Sciences in 2005. It can be obtained through the SCImago Journal Rank web site. It is also possible to calculate an h-Index for individual researchers, although there are problems with it, as described in the articles by Ball, linked below. One of the biggest problems with the H-Index is that it is based on the number of citations. A paper that cites a work as part of a critical analysis to disprove the theories behind it is still citing the original work. Thus, the original work, which has been disproved, could still have a good h-Index.
An Index to Quantify an Individual's Scientific Research Output
Hirsch, J.E., 2005. An Index to Quantify an Individual's Scientific Research Output. Proceedings of the National Academy of Sciences, vol. 102, no. 46, pages 16569-16572.
Achievement Index Climbs the Ranks
Ball, Philip, 2007. Achievement Index Climbs the Ranks. Nature, vol. 448, no. 7155, page 737.
The h-Index, or the Academic Equivalent of the Stag's Antlers
Ball, Philip, 2012. The h-Index, or the Academic Equivalent of the Stag's Antlers. The Guardian, January 6, 2012. Also read the comments on this article, which point out problems with the h-Index.
h-Index: Age and Sex make it Unreliable
Kelly, Clint D. and Jennions, Michael D., 2007. h-Index: Age and Sex make it Unreliable. Nature, vol. 449, no. 7161, page 403.
H-Index: However Ranked, Citations need Context
Wendl, Michael C., 2007. H-Index: However Ranked, Citations need Context. Nature, vol. 449, no. 7161, page 403.

SCImago Journal Rank

SCImago Journal Rank
A measure of the influence of scholarly journals that considers the number of citations received and the importance of the citing journal. The journal rank can be obtained from the Rank section of this website.